topic Re: Convert jpg file to base64 in Talend Studio

Convert jpg file to base64

Dobby1 — Thu, 08 Jan 2026 01:08:53 GMT

I'm using tFileInputRaw to read a jpg file followed by tJavaRow to get the base64 encoding for the file. I get "java.lang.NullPointerException: Cannot read the array length because "src" is null" at the line in the tJavaRow when I attempt to encode the byte array. I've set the Mode for the tFileInputRaw to Read the file as a bytes array. I also tried the other modes without success. Here's the code in the tJavaRow:

byte[] bytes = (byte[]) output_row.content;

//Encode the byte array to a Base64 string

String base64String = java.util.Base64.getEncoder().encodeToString(bytes);

//Pass the Base64 string to the output column

//output_row.base64ImageString = base64String;

Re: Convert jpg file to base64

Shicong_Hong — Thu, 08 Jan 2026 05:48:29 GMT

Hello

To access the input data, here should be input_row.content rather than output_row.content.

byte[] bytes = (byte[]) input_row.content; //Encode the byte array to a Base64 string String base64String = java.util.Base64.getEncoder().encodeToString(bytes);

Regards

Shicong

Re: Convert jpg file to base64

Dobby1 — Thu, 08 Jan 2026 11:48:33 GMT

Hello,

Thank you. I switched to input_row and got the same error at the same line. I then changed the name of the flow between the tFileInputRaw to the tJavaRow2 from "output_row" to row4 and the error disappeared.

Are "input_row" and "output_row" special attributes/properties for a tJavaRow?

Re: Convert jpg file to base64

Shicong_Hong — Tue, 13 Jan 2026 07:05:05 GMT

Hi @Dobby1 if you need to access the input data, should use "input_row.columnName". To assign the data to next component, use "output_columnName".